Android listview点赞问题分析

package com.gz.test_listview;import android.content.Context;import android.content.DialogInterface;import android.content.Intent;import android.os.Handler;import android.os.Message;import android.util.Log;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.AdapterView;import android.widget.BaseAdapter;import android.widget.Button;import android.widget.ImageView;import android.widget.ListView;import android.widget.TextView;import android.widget.Toast;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;/** * Created by gz on 2016/11/9. */public class MainActivityAdapter extends BaseAdapter{//用来获取界面上的元素 private ViewHolder holder; private Context context; //这里的Bean是个测试用的内部类，将点赞数和踩得数存起来，可以定义一个类， //直接获取数据就好，需要改进下 private List<Bean> praise_step_num = new ArrayList<Bean>(); private LayoutInflater inflater; //保存当前点赞数 List<Map<String,Object>> listItems; /* 根据position，保存点击的是哪一行数据，默认为false，点击后改为true */ private Map<Integer, Boolean> isExist = new HashMap<Integer, Boolean>(); public MainActivityAdapter(Context context,List<Map<String,Object>> listItems){ this.context = context; this.listItems = listItems; inflater = LayoutInflater.from(context); Log.i("listItem",listItems.toString()); init(); } private void init() { /* 为相应的数据赋值，所有的数据存储在listItems中 position一一对应每一行数据  */ for (int i = 0;i<listItems.size();i++){  isExist.put(i,false);  Bean b = new Bean();  Integer praise = Integer.parseInt(listItems.get(i).get("praise").toString());  b.setPraise(praise);  Integer step = Integer.parseInt(listItems.get(i).get("step").toString());  b.setStep(step);  praise_step_num.add(i,b);  Log.i("praise_step",praise_step_num.get(i).getPraise()+""); } } @Override public int getCount() { return listItems.size() ; } @Override public Object getItem(int position) { return position; } @Override public long getItemId(int position) { return position; } @Override public View getView(final int position, View convertView, ViewGroup parent) { //获取赞、踩得值 final Bean bean = praise_step_num.get(position); if(convertView == null){  holder = new ViewHolder();  convertView = inflater.inflate(R.layout.item_praise,null);  holder.img_praise = (ImageView) convertView.findViewById(R.id.tv_praises_img);  holder.img_step = (ImageView) convertView.findViewById(R.id.tv_step_img);  holder.praise = (TextView) convertView.findViewById(R.id.tv_praises);  holder.step = (TextView) convertView.findViewById(R.id.tv_step);  holder.title = (TextView) convertView.findViewById(R.id.tv_name);  //holder.img_step.setImageResource(R.drawable.bad);  convertView.setTag(holder); }else{  holder = (ViewHolder) convertView.getTag(); } holder.praise.setText(bean.getPraise()+""); holder.step.setText(bean.getStep()+""); holder.title.setText(listItems.get(position).get("title")+"");  /*  每次会复用convertView,  convertView没有被赋值，就会使用之后赋值的数据，  比如：点击了第一行数据赞的按钮，相应的第一行点赞图片变为红色  当向下滑动页面时，下方的也会有一项数据发生变化，复用  在这里为每次重用赋值  */ if(bean.getPraise()!=0){  holder.img_praise.setImageResource(R.drawable.good); }else{  holder.img_praise.setImageResource(R.drawable.good_no); } if(bean.getStep()!=0){  holder.img_step.setImageResource(R.drawable.bad); }else{  holder.img_step.setImageResource(R.drawable.bad_no); } holder.img_praise.setOnClickListener(new imgClick(position,bean)); return convertView; } class imgClick implements View.OnClickListener { private int position; private Bean bean; public imgClick(int position,Bean bean){  this.position = position;  this.bean = bean; } @Override public void onClick(final View v) {  Log.i("position",position+"");  if(bean.getPraise()==0){  if(isExist.get(position) == false){   final Handler handler = new Handler() {   @Override   public void handleMessage(Message msg) {    super.handleMessage(msg);    switch (msg.what){    case 1:     ImageView btn = (ImageView) v;     if(v.getId() == btn.getId()) {     isExist.put(position, true);     bean.setPraise(bean.getPraise()+1);     btn.setImageResource(R.drawable.good);     AnimationTools.scale(btn);     notifyDataSetChanged();     break;     }    case 2:     Toast.makeText(context, "失败", Toast.LENGTH_LONG).show();     break;    }   }   };   new Thread(){   @Override   public void run() {    Message msg = new Message();    msg.what=1;    handler.sendMessage(msg);   }   }.start();  }  }else{  Toast.makeText(context, "已经点击过", Toast.LENGTH_LONG).show();  } } } private static class ViewHolder{ public ImageView img_praise; public ImageView getImg_praise() {  return img_praise; } public ImageView getImg_step() {  return img_step; } public TextView getPraise() {  return praise; } public TextView getStep() {  return step; } public TextView getTitle() {  return title; } private ImageView img_step; public TextView praise; private TextView step; private TextView title; } class Bean{ public int getPraise() {  return praise; } public void setPraise(int praise) {  this.praise = praise; } public int getStep() {  return step; } public void setStep(int step) {  this.step = step; } private int praise; private int step; }}

package com.gz.test_listview;import android.app.Activity;import android.content.Intent;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View;import android.widget.AdapterView;import android.widget.ListView;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.Objects;public class MainActivity extends Activity { private ListView listview; private String[] title = {"商用","家用","测试","多联","空气能","商用","家用","测试","多联","空气能"}; private String[] praise = {"3","1","0","0","0","3","1","0","0","0"}; private String[] step = {"3","0","0","0","0","3","0","0","0","0"}; private ArrayList<Map<String,Object>> map = new ArrayList<Map<String, Object>>(); private ListView listView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); listview = (ListView) findViewById(R.id.listview); for(int i=0;i<title.length;i++){  Map<String,Object> item = new HashMap<String,Object>();  item.put("title",title[i]);  item.put("praise",praise[i]);  item.put("step",step[i]);  map.add(item); } MainActivityAdapter adapter = new MainActivityAdapter(this,map); listview.setAdapter(adapter); listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {  @Override  public void onItemClick(AdapterView<?> parent, View view, int position, long id) {  Intent intent = new Intent(MainActivity.this,DetailActivity.class);  startActivity(intent);  } }); }}

package com.gz.test_listview;import android.app.Activity;import android.os.Bundle;import android.widget.ListView;import java.util.ArrayList;import java.util.HashMap;import java.util.Map;public class DetailActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.detail_info); }}

package com.gz.test_listview;import android.view.View;import android.view.animation.Animation;import android.view.animation.ScaleAnimation;public class AnimationTools { public static void scale(View v) { ScaleAnimation anim = new ScaleAnimation(1.0f, 1.5f, 1.0f, 1.5f,  Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,  0.5f); anim.setDuration(300); v.startAnimation(anim); }}

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin" tools:context="com.gz.test_listview.MainActivity"> <ListView android:id="@+id/listview" android:layout_width="match_parent" android:layout_height="wrap_content"> </ListView></RelativeLayout>

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/lyt_root" android:layout_width="match_parent" android:layout_height="match_parent" android:background="#ccc" android:orientation="vertical" android:descendantFocusability= "blocksDescendants" > <FrameLayout android:layout_width="fill_parent" android:layout_height="wrap_content" > <ImageView  android:id="@+id/has_exame"  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_gravity="top|left"  /> <LinearLayout  android:layout_margin="10dip"  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:layout_gravity="center_vertical"  android:background="@drawable/corners"  android:layout_weight="1.0"  android:orientation="vertical"  >  <TextView  android:id="@+id/tv_name"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:textSize="14sp"  android:text="商用多联机"  android:textColor="#000"  />  <LinearLayout  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:orientation="horizontal" >  <TextView   android:id="@+id/tv_date"   android:layout_marginTop="10dip"   android:layout_width="match_parent"   android:layout_height="wrap_content"   android:textSize="12sp"   android:text="时间 2016-10-10"   android:textColor="#000"   android:visibility="visible"   />  <TextView   android:id="@+id/tv_downloads"   android:layout_width="wrap_content"   android:layout_height="wrap_content"   android:layout_gravity="center_vertical"   android:layout_weight="1"   android:textColor="#000"   android:textSize="14sp"   android:visibility="gone" />  </LinearLayout>  <LinearLayout  android:layout_width="match_parent"  android:layout_height="match_parent"  android:orientation="horizontal"  android:gravity="center|right"  >  <ImageView   android:id="@+id/tv_praises_img"   android:layout_width="30dip"   android:layout_height="30dip"   android:background="@drawable/good_no"   android:layout_marginRight="5dip"   />  <TextView   android:id="@+id/tv_praises"   android:layout_width="50dip"   android:layout_height="wrap_content"   android:textColor="#000"   android:text="10"   android:textSize="14dip"   android:layout_gravity="center"   />  <ImageView   android:id="@+id/tv_step_img"   android:layout_width="30dip"   android:layout_height="30dip"   android:background="@drawable/bad_no"   android:layout_marginRight="5dip"   />  <TextView   android:id="@+id/tv_step"   android:layout_width="50dip"   android:layout_height="wrap_content"   android:textColor="#000"   android:text="10"   android:textSize="14dip"   android:layout_gravity="center"   />  </LinearLayout> </LinearLayout> </FrameLayout></LinearLayout>

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin" android:orientation="vertical" > <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="111" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="111" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="111" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="111" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="111" /></LinearLayout>